A triangle has side lengths of 2, 6, and 7 units, and a similar but the larger triangle has corresponding side lengths of 6, 18, and 21 units. Calculate and compare the perimeters of the triangles. What is the ratio of the corresponding sides of the smaller triangle to the larger triangle

1 answer

To find the perimeters of the triangles and the ratio of the corresponding sides, we can follow these steps:

  1. Calculate the perimeter of the smaller triangle: The side lengths of the smaller triangle are 2, 6, and 7 units. The perimeter (P) is given by: \[ P_{\text{small}} = 2 + 6 + 7 = 15 \text{ units} \]

  2. Calculate the perimeter of the larger triangle: The side lengths of the larger triangle are 6, 18, and 21 units. The perimeter is: \[ P_{\text{large}} = 6 + 18 + 21 = 45 \text{ units} \]

  3. Calculate the ratio of the corresponding sides: To find the ratio of the sides of the smaller triangle to the corresponding sides of the larger triangle, we take one set of corresponding sides. For example:

    • For side lengths 2 (smaller) and 6 (larger), the ratio is \( \frac{2}{6} = \frac{1}{3} \).
    • For side lengths 6 (smaller) and 18 (larger), the ratio is \( \frac{6}{18} = \frac{1}{3} \).
    • For side lengths 7 (smaller) and 21 (larger), the ratio is \( \frac{7}{21} = \frac{1}{3} \).

    In each case, the ratio of corresponding sides of the smaller triangle to the larger triangle is \( \frac{1}{3} \).

  4. Conclusion:

    • The perimeter of the smaller triangle is 15 units.
    • The perimeter of the larger triangle is 45 units.
    • The ratio of the corresponding sides of the smaller triangle to the larger triangle is \( \frac{1}{3} \).

Thus, the final results are:

  • Perimeter of smaller triangle: 15 units
  • Perimeter of larger triangle: 45 units
  • Ratio of corresponding sides: \( \frac{1}{3} \)